Pure practical reason is the opposite to impure (or sensibly-determined) practical reason and appears in Immanuel Kant's Groundwork of the Metaphysics of Morals.
It is the reason that drives actions without any sensible incentives. Human reasoning chooses such actions simply because those actions are good in themselves; this is the nature of good will, which Kant argues is the only concept that is good without any justification, it is good in itself and is a derivative of a transcendental law which affects the way humans practically reason (see practical philosophy).
Famous quotes containing the words pure, practical and/or reason:
“No one is more dangerous than he who imagines himself pure in heart: for his purity, by definition, is unassailable.”
—James Baldwin (1924–1987)
“No delusion is greater than the notion that method and industry can make up for lack of mother-wit, either in science or in practical life.”
—Thomas Henry Huxley (1825–1895)
“All things have their ends and cycles. And when they have reached their highest point, they are in their lowest ruin, for they cannot last for long in such a state. Such is the end for those who cannot moderate their fortune and prosperity with reason and temperance.”
—François Rabelais (1494–1553)